Change name of GitLab Instance Administrators group

Change name to "GitLab Instance", since we might invite non-admins to
it.
Name change suggested by Sid.

app/models/application_setting.rb

@@ -21,7 +21,9 @@ class ApplicationSetting < ApplicationRecord
   belongs_to :push_rule
   alias_attribute :self_monitoring_project_id, :instance_administration_project_id
 
-  belongs_to :instance_administrators_group, class_name: "Group"
+  belongs_to :instance_group, class_name: "Group", foreign_key: 'instance_administrators_group_id'
+  alias_attribute :instance_group_id, :instance_administrators_group_id
+  alias_attribute :instance_administrators_group, :instance_group
 
   def self.repository_storages_weighted_attributes
     @repository_storages_weighted_atributes ||= Gitlab.config.repositories.storages.keys.map { |k| "repository_storages_weighted_#{k}".to_sym }.freeze

changelogs/unreleased/rp-change-instance-administrators-name.yml

+---
+title: Change name of GitLab Instance Administrators group to GitLab Instance
+merge_request: 41684
+author:
+type: changed

lib/gitlab/database_importers/instance_administrators/create_group.rb

@@ -6,6 +6,8 @@ module Gitlab
       class CreateGroup < ::BaseService
         include Stepable
 
+        NAME = 'GitLab Instance'
+        PATH_PREFIX = 'gitlab-instance'
         VISIBILITY_LEVEL = Gitlab::VisibilityLevel::INTERNAL
 
         steps :validate_application_settings,
@@ -117,12 +119,12 @@ module Gitlab
 
         def create_group_params
           {
-            name: 'GitLab Instance Administrators',
+            name: NAME,
             visibility_level: VISIBILITY_LEVEL,
 
             # The 8 random characters at the end are so that the path does not
             # clash with any existing group that the user might have created.
-            path: "gitlab-instance-administrators-#{SecureRandom.hex(4)}"
+            path: "#{PATH_PREFIX}-#{SecureRandom.hex(4)}"
           }
         end
       end

spec/lib/gitlab/database_importers/instance_administrators/create_group_spec.rb

@@ -65,8 +65,8 @@ RSpec.describe Gitlab::DatabaseImporters::InstanceAdministrators::CreateGroup do
       it 'creates group' do
         expect(result[:status]).to eq(:success)
         expect(group).to be_persisted
-        expect(group.name).to eq('GitLab Instance Administrators')
-        expect(group.path).to start_with('gitlab-instance-administrators')
+        expect(group.name).to eq('GitLab Instance')
+        expect(group.path).to start_with('gitlab-instance')
         expect(group.path.split('-').last.length).to eq(8)
         expect(group.visibility_level).to eq(described_class::VISIBILITY_LEVEL)
       end